The present invention relates to an automobile gear transmission driven by an internal combustion engine, and more particularly to a gear assembly adapted to the gear transmission for eliminating gear knocking noises in operation.
As is well known, there occur gear knocking noises in the gear transmission due to inevitable fluctuation of the engine rotation and backlash of the assembled gears. Such gear knocking noises will occur particularly in idling operation of the engine under the neutral condition of the gear transmission. For the purpose of eliminating the gear knocking noises, as is disclosed in a Japanese Utility Model Publication No. 48-44544, a gear assembly has been proposed which includes a pair of driving and driven gears permanently in meshing engagement with each other to provide a torque transmission therebetween, and an additional plate-like gear relatively rotatable at one side of either one of the gears and being permanently in meshing engagement with the other gear to rotate at a gear ratio different from that of the driving and driven gears, and in which the additional plate-like gear is resiliently in contact with one end face of the gear adjacent thereto to restrain a relative rotation between the driving and driven gears. In such a gear assembly, the additional plate-like gear is eccentrically mounted on a hub portion of the gear adjacent thereto to eliminate backlash between the driving and driven gears. This results in dynamic unbalance of the additional gear, causing another unexpected problem.